What is this pipe on my boiler, and why is it leaking?

In summary, the boiler is leaking, and the leak may be a symptom of a larger problem. The valve needs to be replaced, and there may be a need for a hose to drain the system.
  • #1
DaveC426913
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TL;DR Summary
This pipe is leaking water. Is it supposed to?
A house inspector has noted this leak in our boiler. I don't know what this pipe is for. It seems to have some sort of steam release valve on top and it vents right out onto the basement floor.

Help! Prospective buyers want to know why our boiler is leaking.

boiler.jpg


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  • #2
It is probably a pressure safety valve on a mains pressure hot water system.
The instructions probably say to bleed it momentarily, once a month, to pretect the seat from corrosion, which will result in leaking.
 
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  • #3
That's kind of what I think. Though I know nothing about this stuff.

So, should the fact that it's leaking be a cause for concern?
Does it need to be serviced?
Also, I guess what it needs is a bit of hose that runs to a drain?
What I really need to do is assure the prospective buyers - basically today - that it's been (or being) remediated.
 
  • #4
If it has started to leak, replace it.
No hose is needed, if it does not leak.
The water released, when the lever is operated, soon evaporates.
 
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  • #5
Probably it just has some crud in it. A couple of gallon-size "burps" of water may clear it out (bucket under exit pipe. But replacing it is sure bet. Not hard to do.
I like having the exit plumbing because it makes the mandatory triannual check of the valve mess-freeeee
It should not routinely let water out.
 
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  • #6
Thanks guys. We'll have someone replace the valve.
 
  • #7
Do you notice a steady drip, or does the wet spot appear, dry up, and appear again?

The first is a symptom of a leaky valve, but the latter could be a symptom of the boiler exceeding design pressure. Mine used to blow off like that because there was no expansion tank installed on the cold fill line on the hot water tank.
 
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  • #8
erobz said:
Do you notice a steady drip, or does the wet spot appear, dry up, and appear again?
I didn't even know it was happening. It was the inspector who noted it, obliging me to investigate.
 
  • #10
DaveC426913 said:
Thanks guys. We'll have someone replace the valve.
erobz said:
Mine used to blow off like that because there was no expansion tank installed on the cold fill line on the hot water tank.
Or heating system stopped making heat. I noticed water had leaked out of the same pipe you have leaking. I found that if the system was filled until just before the leaking started that it made heat. I filled it (by lifiting the bail on the city water make up valve) when it was not running. Once the system came up to temperature, excess pressure slowly drove enough water out of system though the pipe that you have leaking and the heat would stop working. I didn't know what the actual cause was so I just kept overfilling it until the repair tech could get to us.

The actual problem was a jammed automatic bleeder valve which caused excess gas in the system.

The solution was to replace the bleeder valve the over-pressure valve and I think the expansion tank. The tech was not happy with my temporary

solution and zip-tied the bail on the valve down.

Make sure the whole system is diagnosed. It may not (only) be the valve that is at issue.

BoB
 
  • #11
rbelli1 said:
Make sure the whole system is diagnosed. It may not (only) be the valve that is at issue.
Yeah, that sounds like a home buyer problem, not a home seller problem. :wink:
 
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  • #12
DaveC426913 said:
Your honor I swear the house became a smoking crater after the signature was dry.
 
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  • #13
Like when the pictures in the sales brochure, become the evidence for the coroner.
 

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